Natural anti clogging Used for continuous letdown...

Natural anti clogging

Used for continuous letdown

Cavitation control

Noise control

Erosion control

Designed using 3Dprediction techniques

XS 4-04072

BlakeboroughX-STREAM™ CONTROL VALVE

Weir Valves & Controls First choice for process protection

Weir Valves & Controls

The key to the success of Weir Valves & Controls isour capability to deliver engineering solutions thatadd value to the customer’s process. We offer a totalpackage of products to meet end-to-end projectrequirements. Using our own analysis andconfiguration system, we will design and deliver theoptimum valves and controls solution to protect thevalue of the production process.

A rigorous programme of information managementmeans that the division is able to take a moreanticipatory role in defining the future needs andexpectations of the market by fully utilising theorganisation's critical resources to provide wholeprocess isolation and control valve solutions for theglobal Energy sector.

With a comprehensive range of engineered valveproducts Weir Valves & Controls have developed anextensive global installed base and expertise acrossa wide range of industry sectors:

• Power Generation• General Industrial• Oil & Gas Production• Refining• Petrochemical• Chemical• Pulp & Paper• Desalination

XS 4-0407 3Weir Valves & Controls First choice for process protection

Blakeborough X-STREAM™ CONTROL VALVE

Quality assurance

Weir Valves & Controls operates quality programmesto cover the full scope of their activities.Comprehensive quality systems have beendeveloped to serve the power, oil and gas andindustrial markets which they serve.

The company holds approvals to:

• ASME Section III ‘N’, ‘NPT’

• ASME Section I ‘V’

• ASME Section VIII code UV

• BS EN ISO 9001:2000

• API Q1 TO API LICENCES API 6D (6D-0182) ANDAPI 6A (6A-0445)

The Quality systems have been approved for thesupply of products to meet the requirements of thePressure Equipment Directive (PED) and compliancemodules A,D1,H,B&D have been applied incategories I through IV respectively.

The company is committed to compliance withlegislation and has an established environment andhealth and safety policy.

Valve testing facilities

All pressure containing items are hydrostaticallytested, seat leakage tested and functionally tested.In addition, gas, packing emission, cryogenic andadvanced functional testing can be arranged.

Material testing facilities

• Non-destructive examination by radiography,ultrasonics, magnetic particle and liquidpenetrant.

• Chemical analysis by computer controlled directreading emission spectrometer.

• Mechanical testing for tensile properties atambient and elevated temperatures, bend andhardness testing. Charpy testing at ambient,elevated and sub-zero temperatures.

Further technical information can be obtained fromour Web site: http://www.weirvalve.com

CONTENTS

What is a Severe Service Application 4

Summary of Product Range 4

X-Stream™ Trim 5

How the X-Stream™ Works 6 - 9

Gas Applications 10 - 11

Severe Service Applications 12 - 13

Vari-Stage Trim 14

Basic Specification 15

Bonnet Forms & Seal Rings 16

Tables 17 - 19

Blakeborough ControlsThe Control Valve business unit have designed andmanufactured valves for in excess of 50 years. Theircontrol valve product range offers an extensivechoice in terms of size, pressure class, body/trimmaterials, and includes top, top & bottom guidedand cage guided valves. In addition they also supplya wide range of desuperheating equipment tosatisfy power and steam conditioning applications.

6A-04456D-0182

X-Stream™

Size Range

Pressure Class

Body Configuration

Cv Range

Valve Characteristic

No. of pressure letdown/velocity control stages

Leakage Class

Connection Type

Bonnet Style

Packing Type

Plug Design

Body Material

4 Weir Valves & Controls First choice for process protection


XS 4-0407

There are many definitions as to what is and is notconsidered to be a severe service application, whichmakes applications difficult to identify for valvemanufacturers and customers alike. An applicationis therefore generally recognised as severe serviceeither through past experience of problemsassociated with similar applications or because thepressure drop which the valve is required to handledefines the need for a specialist ‘severe service’control valve as per the valve manufacturersrecommendations. Unfortunately, this second pointis highly dependent on the product range offeredby a particular manufacturer to the point where anapplication may be considered severe service byone manufacturer but not by another.

However, in an attempt to clarify what is and is nota true severe service application, Weir Valves &Controls found that most applications appear to fallinto one of two categories, which are as follows;

• applications where there is a high pressure drop across the valve (for example in excess of 150 bar)

or

• applications where there are likely to be problems, such as cavitation, high fluid velocitiesor noise.

What is a Severe Service Application?

Severe service applications are consideredproblematic because of typical problems which arefound with the control valves fitted in these services.The valves are more susceptible to problems withinthese severe environments because of the largeamount of potentially destructive energy whichmust be removed from the fluid flow as it passesthrough the valve. Typical problems include;

• high fluid velocities

• excessive noise

• cavitation

• severe erosion

• vibration

• seat leakage

• poor flow control and general valve stability

Some valve manufacturers have a tendency to overspecify their control valves because they don’t havea full range of trim options. Blakeborough have awide range of trim configurations that will satisfyvirtually every set of process parameters, thereforethe optimum trim configuration is selected. TheX-StreamTM trim is specifically designed to controlthe most severe of applications, in liquids it is usedto eliminate cavitation and erosion through velocitycontrol. In gases it is used to control noise.

2'' (50 mm) to 30'' (750mm), 1'' (25mm) also available but please consult factory for information

ANSI Class 150 to 4500 & PN10 to PN640 (consult factory for equivalent metricand other non standard pressure classes available)

Globe & Angle Valve (Globe: BV500 & BV990, Angle: BV501 & BV992)

4us to 500us depending on valve size (consult factory for special designswhich require higher or lower Cv’s

Linear, Modified Linear, Modified EQ%, Customised.

Continuous resistance trim with equivalent of up to 60, specialist design available

Up to Class V shut-off

Buttweld, Flanged, (Standard), Socket weld, Screwed (1''only) & Hubbed

Standard, Normalising & Cryogenic

PTFE Chevron, Graphite

Solid, Balanced

Carbon Steel; Grade WCB, LCC Stainless Steel; Grade 316/304/347,1.1/4% Chrome Moly. Steel; Grade WC6, 2.1/4% Chrome Moly. Steel;

Grade WC9, Monel, Aluminium Bronze, Hastelloy B/C, Duplex & Super Duplex,other materials available from Weir Foundry - Please consult factory for details.

Summary of Product Range

Blakeborough X-STREAM™ SEVERE SERVICE CONTROL VALVE TRIM

The new Weir Valves & Controls X-Stream™ trimhas been specifically developed to eliminate theproblems of erosion, cavitation and noise on bothsevere and problematic services. Through its uniqueflow path design the X-Stream™ trim is the first of itskind to provide '3D-flow control' within the fluidflow as it passes through the valve. The X-Stream™trim is able to ensure superb fluid control andcontinued reliability through a more accurate andthorough prediction of the fluid flow through thevalve.

Available in a range of materials the X-Stream™ hasbeen designed with long term reliable service andease of maintenance in mind.

Features & Benefits

• The X-Stream™ trim is a continuous letdown,cage guided trim design, for both liquid and gassevere service/high pressure applications.

• X-Stream™ is designed using the principles of 3DFlow Control to ensure that damaging fluidproperties such as high stage pressure gradients,fluid velocity and kinetic energy are kept to aminimum by controlling areas of excessive fluidre-circulation and damaging flow separation inthe trim.

• The unique X-Stream™ flow path can be designedwith an equivalent of up to 60 stages of pressureletdown, when compared to severe service valvesfitted with a sharp turn, tortuous path cagedesign.

• The X-Stream™ can be designed to provide a widevariety of dynamic performance characteristicsfrom standard linear, equal percentage to customdesigned characteristics.

• X-Stream™ flow path contains a natural selfcleaning/anti-clogging flow path suitable fordirty/contaminated services resulting in reducedmaintenance time and costs.

• The X-Stream™ trim is designed to beincorporated into the BV500 and BV990 range ofvalves.

• X-Stream™ can be retrofit into existing valvessupplied by both Blakeborough (BV500 andBV990 range) and other control valvemanufacturers.

• The X-Stream™ can be fitted into valves rangingfrom 2" (50 mm) to 30" (750mm).

• X-Stream™ is designed so that all maintenancecan be done on site.

• The X-Stream™ trim is supplied with a weldeddisc stack that is clamped into the body using thetraditional 3 gasket clamp arrangement. Onapplications where there is a strong potential forblockage due to line debris, the trim can besupplied with separable discs. In this case aspecial body configuration is required.

Recommended Applications

• Choke Valves

• Minimum Pump Flow Re-circulation

• Anti Surge

• Boiler Feedwater

• Attemperator Spray Valve

• Overboard Dump

X-Stream™ Trim detail, patent applied for.

Velocity profilePressure drop profile

A new technologically advanced valve trim for extremeprocess conditions from Weir Valves and Controls

5Weir Valves & Controls First choice for process protectionXS 4-0407

BlakeboroughHOW THE X-STREAM™ WORKS - ‘3D’ FLOW CONTROL

Controlling fluid formations

As well as providing a method by which the overalldesign of the valve trim can be improved to moreeffectively handle the fluid flow, 3D Flow Controlalso allows the effect of any three-dimensional fluidformations within the flow to be understood andcontrolled by providing additional and moreaccurate information which can then be easilyincorporated into the standard valve sizingprocedures.

With the addition of these 3D Flow Controlparameters in the standard control valve sizingmethodology, each X-Stream™ trim is designed tomaximise performance for each and every set ofprocess conditions supplied. With a pressure dropcapability of the equivalent to 60 stages of letdownthe X-Stream™ is capable of safely handling pressuredrops of up to 400 bar and, on liquid flows, outletpressures that are very close to the vapour pressureof the line fluid without the onset of cavitation.

The advantages of 3D flow control and theX-Stream™ trim

The X-Stream™ trim is the first in a new andadvanced generation of control valve technology,designed to manage the most severe of processenvironments with continued safe and reliableoperation. The X-Stream™ trim owes its superiorperformance to an extensive research anddevelopment program, which has resulted in thebirth of a new design methodology known as ‘3DFlow Control’. This new technique has been used tospecify the X-Stream’s unique design and flow pathconfiguration to ensure that the valve providesoptimum performance in service.

Controlling a new dimension

Severe service applications are notorious forcausing problems in the control valves responsiblefor handling these arduous conditions. Typicalproblems include poor flow stability, cavitation,erosion (often first seen in the form of seat leakage)and excessive noise and vibration, all of which canhave significant effects on the successfulperformance of the valve. However, although theseproblems appear varied, in most cases they can beattributed to a poor control of the fluid flow as itpasses through the valve, leading to high pressuregradients, high fluid velocities and damaging levelsof kinetic energy within the fluid flow.Consequently, a typical severe service control valvewill use a number of stages of letdown (eitherthrough a labyrinthine style flow path or through aconcentric sleeve type cage design) to reduce thepressure drop across each stage, resulting in areduction of both the fluid velocity and kineticenergy levels. Unfortunately, this simplistic one-dimensional approach to the problem does not takeinto account the three-dimensional formation of thefluid flow as it passes through the valve. Recentresearch has shown that this can be just asdamaging if left uncontrolled.

No sharp corners

The primary feature of the X-Stream™ trim is the valvecage, a disc stack cage configuration thatincorporates a series of flow paths in which arelocated an array of staggered cylinders. By forcing thefluid through these tightly packed cylinder arrays, theflow is passed through a labyrinthine tortuous pathwhich is able to dissipate the fluid energy efficientlywith limited pressure recovery between stages andwithout the unnatural movement of the flow aroundsharp angled corners, such as those found in othersevere service trims on the market. This type ofunnatural movement has been found to result innumerous problems due to uncontrolled three-dimensional fluid formations within the flow, such asseparation and areas of re-circulation.

6 Weir Valves & Controls First choice for process protection XS 4-0407

Blakeborough HOW THE X-STREAM™ WORKS - ‘3D’ FLOW CONTROL

Bringing in the third dimension

In order to see the distinct benefits of the X-Stream™trim and the methodology used we haveincorporated this in-depth section which describesthe research behind the design.

How the X-Stream™ Works – ‘3D’ Flow Control

The X-Stream™ incorporates a uniquely designedcontinuous resistance flow passageway tobreakdown the total pressure drop into muchsmaller stages by passing the flow through atortuous array of tightly packed cylinders. Thisincreases the resistance to the flow provided by thepassageway and therefore the valve trim, thusreducing the fluid velocity. However, unlike othersevere service control valves on the market, the X-Stream™ is designed and sized using themethodology of ‘3D Flow Control’.

The X-Stream’s unique continuous resistance flowpassage arrangement is the result of a 5 yearresearch and development program and has beendesigned using modern computational andexperimental analysis equipment. These advancedtechniques enable detailed understanding of howthe complex, tortuous flow paths used in othersevere service trims were able to handle the highpressure drops across the trim. It became clear thatthe fluid flow through the passageways in the valvetrim were subject to high levels of turbulence and anumber of complex three-dimensional fluidformations such as areas of re-circulating flow,vortices and jet formations. The presence of thesedisturbances was leading to a wide variation in boththe local static pressure and velocity profilesthrough the flow path.

Unseen velocity increases of up to 50%missed using normal sizing calculations

Further investigation revealed that the cause ofthese three-dimensional formations was, in themain, due to the complex geometry of the valve.For example, sharp, right-angled turns were leadingto large areas of re-circulating flow in the outwardfacing corners. This not only created an area of lowstatic pressure which, on liquid flows, could lead tothe early onset of cavitation, but also reduced thehydrodynamic area of the flow path leading to veryhigh fluid velocities. These were exacerbated furtheras the areas of high fluid velocity were forced toseparate off the inward facing corners as shownabove. It was found that this large variation in thelocal fluid velocity level caused the maximumvelocity in the flow path to increase by up toapproximately 50% of that predicted by traditionalone-dimensional control valve sizing methods.

As a result of these findings, the X-Stream™ flowpassage has been designed to provide a much more‘curved’ flow path; following the natural movementof the fluid flow in order to reduce the presence of

these detrimental three-dimensional fluidformations. The close proximity of the cylinders toeach other means that the energy is released fromthe fluid through safely contained interactions andcollisions with itself, rather than the internal walls ofthe passageway which can lead to excessive erosionif left uncontrolled and seriously reduce the lifetimeand performance of the trim. As well as reducingthe presence of unsteady three-dimensional fluidformations both the local static pressure and thefluid velocity are controlled more evenly throughthe flow passageway. This results in an overallreduction in the maximum fluid velocity of around30%, based on the test results conducted duringthe research programme.

Velocity profile through a competitors‘severe service’ trim flow path.

Velocity profile through the X-Stream™.


Failedlabyrinth disc

BlakeboroughHOW THE X-STREAM™ WORKS - ‘3D’ FLOW CONTROL

CFD identifies cavitation potential wherestandard methodology fails

Its unique flow passage design also provides theX-Stream™ trim with its self-cleaning capabilities, byallowing small particles to pass through the flowwithout obstruction, preventing particle build-upwhich can eventually lead to the flow pathsbecoming blocked and inevitably valve failure. Thevalve trim is also designed so that it can be easilymaintained on site and, where possible, a separabledisc stack gives maximum flexibility. In addition toproviding a superior valve trim design, the X-Stream™ is able to go one step further by applyingthe methodology of ‘3D Flow Control’ to the sizingand selection of the valve.

Whilst the X-Stream™ has a significantly improvedflow path which is better able to control the fluidvelocity, static pressure and prevent the onset ofcavitation there are still three-dimensionalformations within the fluid flow which can effectthe performance of the valve.

Whilst these three-dimensional formations exist,accurate fluid velocities are almost impossible topredict using the oversimplified one-dimensionaltheory which forms the basis of most existingcontrol valve sizing methods. This also means thatrelating properties such as the local static pressurelevels, temperature and fluid density used topredict the presence of cavitation or high levels ofnoise will be subject to some degree of inaccuracy.Some manufacturers will claim that whilst this istrue, the level of this inaccuracy is so small that itdoes not warrant further complication of existingsizing methods. However, although this may beacceptable for simple control valves, such as thosefitted with single-stage trim devices like theBlakeborough multi-flow or contour trim. Forhighly complex severe service trims the researchconducted by WVC UK indicated that this is not asafe assumption.

The investigation used two prediction techniquesto determine the onset of cavitation within anX-Stream™ trim: the first using computational fluiddynamics (CFD) to predict the points at which thelocal static pressure fell below the minimum staticpressure, and the second, was based on the sameprinciples used in existing one-dimensional sizing

techniques. The results were then compared withthe cavitation damage on an actual valve trimunder the same conditions. Under the one-dimensional prediction technique an average levelof static pressure was assumed which, whencompared with the fluid vapour pressure, wasfound to be higher suggesting no cavitation wouldoccur. Using the three-dimensional technique(CFD) suggested local areas of cavitation attachedto the sides of the cylinders, comparing very wellwith the actual damage seen on the prototype trim.

Whilst it is not practical to conduct a CFD analysison every severe service control valve in order for itto be correctly sized, this evidence highlights thesources of error within existing one-dimensionalcontrol valve sizing theory and the importance ofunderstanding how the individual geometricalaspects of the valve can affect performance: forexample, changing the diameter or spacing of theholes in the concentric sleeve trim.

Example of cavitation damage prediction using CFD.

Comparison of predicted damage to actual damage.


• The X-Stream™ trim is designed to minimisesections of high velocity so the velocity gradientis spread across the trim profile.

• Jet impingement causes pressure reductionwithout the negative effects of trim damage.

9Weir Valves & Controls First choice for process protection

Blakeborough X-STREAM™ CONTROL VALVE

XS 4-0407

• In trims with a tortuous path there are large areasof re-circulating flow. When debris is present inthe flow these areas can cause blockages.

• In trims with a tortuous flow path localisedsections of high velocity can cause prematureerosion and loss of control.

• The X-Stream™ trim is designed with smooth flowpaths to minimise the areas of re-circulating flowand eliminate localised high velocity.

Area of re-circulating flow

Localised highvelocity

Pressure profile through the X-StreamTM


BlakeboroughX-STREAM™ FOR GAS APPLICATIONS

XS 4-0407

Gas Noise Reduction

Much research has been undertaken into the theoryof shock cell formation in gas flows. It is the shockcell formation and jet interaction that creates highnoise levels. In a cage trim valve the size of the exithole is a crucial factor in determining the noise levelgenerated. On large holes shock cells are generatedwhich propagate outwards. As the cells coalescethey produce larger shock cell formation which inturn generates higher levels of noise.

It therefore follows that the best method of reducingvalve generated noise is to prevent the shock cellscoalescing by spacing the jets wider apart.��

��

In developing the X-Stream™ for gas applicationsseveral disc patterns were modelled using the 3Dcomputerised fluid dynamics models as describedfor liquid applications. Velocity profiles of gasespassing through the pattern of columns wereanalysed to establish the best velocity profile to beemployed. The CFD model of the most effectiveflow path is shown below.

Pressure Profile

Mach Number Profile


Blakeborough X-STREAM™ FOR GAS APPLICATIONS

XS 4-0407

The disc is designed so that the gas pressure isreduced gradually over many cylinder arrays. Higherpressure drops are controlled as the gas enters thedisc where the cylinders are tightly packed. As thegas flow passes towards the outlet of the disc thecylinder size is reduced giving reduced pressuredrops. The final row of cylinders controls the gasjets, it is this row that prevents shock cellcoalescence as the flow exits the trim. TheScherlieren visualisation for the above disc is shownbelow, it can clearly be seen that shock cells havebeen totally eliminated at the exit of the trim.

Discs of various numbers of cylinder arrays werethen tested, and those which demonstrated the bestresistance to shock cell formation is shown below.

Even distribution of the gas jets eliminating pressure pulses.

Scherlieren testing

To establish the integrity of the CFD modelling,various flow paths were tested using Scherlierenoptical techniques to visualise the light intensity ofthe shock cells, jet formations and vortices.Scherlieren techniques work by highlighting thechanges in density within a flow which deviate thelight rays passing through the boundaries. Light isprovided by a high intensity light source and theimage it creates is reflected into a camera usingmirrors and a knife edge.

To establish a datum measurement a blank disc wastested to simulate a single stage trim and theScherlieren visual image was produced as below.The shock cell formation can clearly be seen and it isthese pulses that would be responsible for highnoise levels if this type of disc was used in a workingcontrol valve.

Light Source

Pipe

Mirror

Field of View

Fluid Flow

Image Direction Lens

Knife Edge

ImageFocusing

Box

Camera

Mirror

Blank disc simulates single stage trim

It can be seen from the image below that shock cellswere created in the gas. The shock cells wouldgenerate high noise levels in the downstream pipe.

Disc with jet control row

BlakeboroughX-STREAM™ SEVERE SERVICE APPLICATIONS

Severe Service Applications

Severe service applications are very difficult todefine and are normally specified throughexperience, as problematic, rather than applicationsabove a certain level of pressure drop. For example,a valve with 100 bar pressure drop across it wouldnot necessarily be classed as high pressure, butcould still be considered severe service if the outletpressure was only slightly above fluid vapourpressure. However, applications with pressure dropshigher than around 300 bar would normally beclassed as problematic and therefore severe service.This is because of the potential of fluid velocitieswithin the valve and the greater probability forcavitation/flow erosion to occur. These applicationscan be handled by carefully controlling the energydissipation within the valve. It is this process whichgives the high-energy loss trims their name.

In an attempt to give a clearer understanding of thetypes of applications which can be consideredsevere service some examples from the power andoil and gas industries are listed below.

Power Industry

The type of valve used in the power industrydepends on the types of station. The followingexamples are based on a modern combined cyclepower plant.

The Condensate System

This covers the process from the condensor to thedeareator and essentially acts as a heat exchangerby condensing the steam from the turbine so that itcan be recycled through the system. A partialvacuum in the condenser helps to lower the outputpressure for the turbine therefore increasing itsefficiency. The output from the condenser is thenpassed through a series of low-pressure heaters,which will be used to lower the temperature of thefluid still further, before it is passed into thedeaerator. Because of the low pressure in the systemthere is only one valve, which could potentially beconsidered as severe service, this is the condensateRe-circulation valve.

Condensate Re-circulation Valve

To protect the condensate pump from overheatingand cavitating, it is necessary to ensure there is aminimum amount of fluid flowing through it.When re-circulation is necessary the condensate re-circulation valve is used to dump the condensateinto the condenser, which is either at atmosphericpressure or even a partial vacuum. Although typicalpressure drops would only likely to be in the regionof 30-40 bar (400-600 psig) because of the lowoutlet pressures there is a high potential forcavitation.

The Feedwater system

This system, encompasses the portion of the steamcycle that takes the feedwater from the deaeratorand passes it through the boiler feedwater pumps,high-pressure heaters, the economiser and into theboiler. During this process the feedwater is heatedto the temperature of the boiler and raised to its fulloutlet pressure. This system is regarded as the mostsevere environment in the plant and the severeservice valves are normally located around theboiler.

Boiler Feedwater Re-circulation Valve

This controls the re-circulation system used toprotect the boiler feedpump from its severe serviceenvironment. As the differential pressure betweenthe boiler and the deaerator is relatively high, thevalve is likely to see high pressure drops across it.Because of its usage levels this is probably one ofthe most severe applications within the plant andtypical conditions depend very much on the size ofthe plant. For example these may be as high as inletpressures of 380 bar (5500 psig) with outletpressures of 0-10 bar (0 – 150 psig).

Boiler Feed System

For start up, the boiler feed system must cope withthe full pressure of the feedpumps at the inlet andthe unpressurised boiler at the outlet, with relativelysmall flow rates. However as the boiler drum comesup to pressure, the pressure drop across the systemreduces and the flow rate increases. With the twovery different sets of process conditions, two valvesare normally used in parallel with each other toachieve this large rangeability. These are unique todrum style boilers and, dependant on the boilermanufacturer, may not be control valves. It is thestart-up valve which is likely to see severe serviceprocess conditions.

Boiler Feedwater Start-up Valve

During start-up the flows are usually very small withthe high pressure drops and hence the potential forcavitation is high, however, its severity is not asgreat as that seen by the boiler re-circulation valve.Inlet pressures are likely to be in the region of 200-220 bar (2800-3200 psig) with outlet pressures nearatmospheric.

The Main Steam System

This takes the high pressure steam from the boilerand sends it through the superheaters into the high-pressure turbines. The steam is then bled off,pumped through a reheater and passed into the lowpressure turbine, before finally being dumped intothe condenser after all its potential has beenextracted. Because of the high pressure steam inthis system, several of the valves can be classed assevere service.


Reheater Atterperator Spray Valve

Used to control the temperature of the steam beforeit enters the low pressure turbine, which is critical toprotect the delicate turbine blades from beingdamaged. In this case the reheater is maintained ata relatively low pressure and the relatively highpressure drops combined with low flow rates give ahigh potential for cavitation. Inlet pressures can beas high as 270 bar (3900 psig) with an outletpressure of 2 bar (290 psig)

Deaerator Pegging Steam Valve

The deaerator pegging steam valve is used tosupply the deaerator with the water it requires,which means a high-pressure drop with thepotential for severe noise generation. Similar to theturbine bypass valve, typical conditions include inletpressure of up to 310 bar (4500 psig) and outletpressures close to or at atmospheric pressure.

Soot Blower Valve

Used to control the sootblowers, which are used tokeep the boiler tubes clean. This applicationexperiences high pressures and pressure drops,which are likely to cause a noise problem. Typicalconditions include inlet pressures of up to 310 bar(4500 psig) and outlet pressures close to or atatmospheric pressure.

Oil & Gas Applications

Oil and gas refinery/processing is a notoriouslyarduous service for any of the major processcomponents therein. This is due to theenvironments in which the valves are situated andthe type of services which they are likely to see. Oiland gas will normally occur in the same place andtherefore, when trying to extract it, it is likely thaton occasion both fluid and gasses will be capturedtogether creating what can be a highly erosive two-phase flow. When this is combined with theextremely high pressures at the well head andentrained particles of sand, it can prove to be one ofthe most arduous process conditions ever seen bycontrol valves. Another highly corrosive service issour gas, where the gas is polluted with hydrogensulphide, which is highly corrosive. Also, sub-seavalves must be able to withstand corrosion from thesalty seawater and hot services are becoming moreof a problem, particularly in the area of the wellhead. Unlike applications in the Power industry,valves for oil and gas applications can varyextensively between sites, which make them verydifficult to standardise.

Re-circulation Valves & Overboard DumpValves

Similar to the minimum flow re-circulation valves inpower applications, these valves re-circulate fluidthrough the pumps, as it is impractical to have thepumps running at low levels. The excess fluid isthen dumped overboard. Because of this, the valveswill be seeing high pressures from the pump at theinlet and outlet pressures at atmospheric vent. Withsuch a combination of high pressure drops and lowoutlet pressures the potential for cavitation is high.

Separator Level Controls

This is the second valve seen by the excavated fluid,the first being the choke valve. It is therefore likelyto see relatively high pressure drops with multi-phase flow, which is a mixture of gas, oil and water.Entrained sand can also be present in the mixtureon some old services.

Flare Valves

These valves are used to control the venting of theexcess hydrocarbon gas and will thereforeexperience high pressure drops as the gas is takenfrom a high pressure system and vented intoatmosphere. However, because the fluid ishydrocarbon gas the service a relatively clean.

Anti-surge Valves

The anti-surge valves are attached to both the highand low pressure systems and are used to protectthe gas compressors from unwanted surges. Likethe pump re-circulation valves, these valves arelikely to see high pressure drops with outletpressures at near atmospheric conditions. In thiscase the valves operate on gas services andtherefore noise and vibration are the mainproblems.

Glycol & Methanol Systems

Glycol and Methanol are used in the system to cleanout the water from the pipework and pipingcomponents to prevent them from icing up in coldconditions. Because this is a flushing process over alarge length of pipework the fluid must be pumpedat high pressures but will be reducing to lowpressures at outlet, therefore cavitation potential ishigh.

Oil Export Pump Valves

These valves are used to control the pumps whichare used to export the oil down the piping systemand to shore, where it can be processed. Thisservice is problematic because it is likely to see highpressures with high flow rates, therefore thepotential for cavitation is high. However a commonproblem with this type of service is vibration.

Blakeborough X-STREAM™ SEVERE SERVICE APPLICATIONS


BlakeboroughX-STREAM™ VARI-STAGE TRIM

Recent feedwater applications have been quitechallenging due to the need to control cavitation atlow valve openings, but yet pass the flow capacityat higher valve openings.

When filling the boiler on a power station there isgenerally a high pressure at the valve inlet, but alow outlet pressure, often only 1 bar. This conditionwould result in severe cavitation if a single stagetrim was to be applied. Using the X-Stream™ trimthe pressure drop is staged across the disc whichprevents the static pressure falling below thevapour pressure, thus eliminating cavitation andprotecting the valve and the trim from damage.

When the plant is running, the boiler is chargedand the feedwater valve is required to maintain thewater flow rate into the boiler. This conditionwould normally require high flow rates, butrelatively low pressure drops resulting in lowcoefficients.

Historically power stations would be built with twovalves working in split range operation, one onboiler fill designed to control cavitation and one fornormal operation to control flow. The demand forcost reduction in power station construction nowmeans that engineers are demanding one controlvalve to fulfil both these applications.

To specifically address this applicationBlakeborough have developed the X-Stream™ Vari-stage trim. This trim has been designed using thepatented X-Stream™ disc stack at the bottom of thetrim to control low valve Cv’s and eliminatecavitation, but at higher valve openings the valvetrim is designed with a more standard multi-flowtrim to obtain the flow capacity.

The picture shows a sectioned view of the X-Stream™Trim. The lower section of the trim is designed with8 discs stacked together and vacuum welded ontoa multi-flow cage.

This design can be incorporated on applicationswhere multi-stage control is required at low valveopenings, but where higher capacities are requiredat higher valve openings.



Blakeborough X-STREAM™ TRIM

XS 4-0407

Versatility

Blakeborough offer a wide choice of options to meetmost system requirements, eliminating or greatlyreducing the multiplicity of valve designs that wouldotherwise be required.

This flexible range of valves offers an extensiveselection of trim designs, materials and sizes, and istherefore able to meet the ever increasing demandsof modern day plant. All parts are interchangeablebetween globe and angle style valves in a given sizeand pressure rating.

Parts substitution, internal inspection andmaintenance are effected with minimum trouble,the essential working components being removablewhile the body remains undisturbed in the pipeline.

• Simple, low cost, in line maintenance

• Comprehensive interchangeable parts systems

• High-stability plug guiding

• High flow capacity

Main design standards

• ASME B16.34 – Valve – Flanged, Threaded &Welded Ends

• ANSI FOCI 70-2 – Control Valve Seat Leakage

• ASME B16.25 – Butt Weld Ends

• ASME B16.5 – Pipe Flanges & Flange Fittings

• NACRE MR-01-75 ISO 15156 Valve Materials(option)

• BS1560 – Circular Flanges for Pipes, Valves &Fittings

• BS4504 – Circular Flanges for Pipes, Valves &Fittings

Features

Pressure Ratings

• ANSI Class 150lib to 600lib (BV500 Series)

• ANSI Class 900lib to 4500lib (BV990 Series)

• Equivalent metric pressure ratings

Body

• A choice of globe or angle patterns available

• BV500 & BV990 Globe body

• BV501 & BV992 Angle body



XS 4-0407

Normalising

Standard

PTFE Chevron Grafoil

Bonnet forms

Standard

For applications where the temperature of thecontrolled fluid is between -18˚C (0˚F) and 232˚C(450˚F). May be used with graphite packing up to315˚C (600˚F). Although modern packagings aresuitable for much higher temperatures it isrecommended that the normalising bonnet be fittedin cases where the temperatures exceed the abovevalues to accommodate lagging of the control valvebody.

Normalising

For protection of the gland packing at temperaturesabove 232˚C (450˚F) and below -18˚C (0˚F) downto -100˚C (-150˚F). The bonnet is designed with finswhich dissipate the heat from process fluid and helpprotect the Packing and actuator assembly fromhigh temperatures. In addition the normalisingbonnet is longer than the standard plain bonnet sothat the valve can easily be lagged withoutinterference with the actuator.

Cryogenic

Used for temperatures below -100˚C (-150˚F). Thebonnet designed with a long necked section whichdistances the packing away from the process fluid.The necked section is designed with a minimumwall section to minimise heat transfer. Cold boxextension/cryogenic bonnets are also available.

Cyrogenic

Packing

Packing are selected based on fluid temperature andfluid type. The most common packing systemmaterials are PTFE for low temperature and graphitefor high temperature. Low emission packing areavailable which have been tested to prove emissionlevels of less than 500 parts per million over 50,000cycles and under thermal cycling conditions.

PTFE Chevron

is used for applications where the temperature isbetween cryogenic to 232˚C (450˚F)

Grafoil

is used on high temperature applications where thetemperature exceeds 232˚C (450˚F)

Other packing types can be accommodated asrequired.

Seal Rings

On balanced design valves the valve plug isdesigned to incorporate a seal ring which preventsleakage around the periphery of the valve plug.Depending upon the desired leakage andtemperature through the valve a variety of seal ringsare specified.

Carbon Ring Triple Seal Ring

‘U’ Seal

Blakeborough X-STREAM™ TABLES


Table 1 – Materials of construction

*options for Stellite face or full Stellite available for most materials.TC = Tungsten Carbide

Table 2 – Leakage glass

Table 3 – Recommended limiting velocities

Note: Maximum outlet velocity (steam or gas) = 0.65 x sonic

Leakage Class Seal Ring Material Temperature

Class 111 Carbon Graphite -35˚C (-30˚F) to 565˚C (1050˚F)Class IV & V Carbon PTFE ‘U’ Seal -176˚C (-30˚F) to 260˚C (500˚F)Class IV & V High temp ‘U’ Seal 260˚C (500˚F) to 300˚C (572˚F)Class IV & V Virgin PTFE ‘U’Seal Cryogenic to -35˚C (-30˚F)

Class IV Carbon Triple Seal 350˚C (660˚F) to 565˚C (1050˚F)

Metric Units US Units

Body Size (MM) Liquid (M/S) Steam or Gas (M/S) Body Size (IN) Liquid (FT/S) Steam or Gas (Ft/S)

40, 50 13.5 150 1 1⁄2, 2 44 49080, 100 13.5 150 3, 4 44 490

150, 200, 250, 300 13.5 150 6, 8, 10, 12 44 490350, 400, 450, 500 12 130 14, 16, 18, 20 39 425

≥600 8.5 120 ≥24 28 390

Cage Plug Disc Plug Stem Seat Service

316 ST.ST. 17-4PH ST.ST. Hardened Inconel 316 ST.ST./ 316 + Stellite -35˚C to 399˚C718 718 -30˚F to 750˚F

316 ST.ST. 316 ST.ST. with - - 400˚C to 565˚CStellite face & Guide - - 750˚F to 1050˚F-

Duplex Duplex Duplex Integral with Cage/Duplex -316 ST.ST. 316 ST.ST. + Ceramic 316 ST.ST. 316 ST.ST. + Ceramic -

316 ST.ST. + TC 17-4PH ST.ST. + TC 316 ST.ST. 316 ST.ST. + TC -Duplex + TC Duplex + TC Duplex Duplex + TC -


BlakeboroughX-STREAM™ TABLES

XS 4-0407

Table 4 – X-Stream™ Trim Design CV

*Trims for two phase flow are available on request.

Valve Series Valve Size Design Cv Flow Direction Trim Size Flow Characteristic Travel (mm) Rangeability

500/501 50 4 Under X13 Mod Eq% 28.5 30500/501 50 6 Under X13 Linear 28.5 30500/501 50 6 Under X13 Mod Eq% 38 30500/501 50 7 Under X13 Linear 38 30500/501 80 7 Under X15 Mod Eq% 38 40500/501 80 9 Under X15 Linear 38 40500/501 80 10 Under X15 Mod Eq% 57 40500/501 80 14 Under X15 Linear 57 40500/501 100 15 Under X15 Mod Eq% 57 45500/501 100 22 Under X15 Linear 57 45500/501 150 31 Under X19 Mod Eq% 89 50500/501 150 48 Under X19 Linear 89 50500/501 200 39 Under X21 Mod Eq% 89 55500/501 200 58 Under X21 Mod Eq% 127 55500/501 200 59 Under X21 Linear 89 55500/501 200 73 Under X21 Mod Eq% 152 55500/501 200 86 Under X21 Linear 127 55500/501 200 102 Under X21 Linear 152 55500/501 250 63 Under X21 Mod Eq% 89 60500/501 250 89 Under X21 Linear 89 60500/501 250 92 Under X21 Mod Eq% 127 60500/501 250 115 Under X21 Mod Eq% 152 60500/501 250 129 Under X21 Linear 127 60500/501 250 154 Under X21 Linear 152 60500/501 300 75 Under X21 Mod Eq% 89 65500/501 300 111 Under X21 Mod Eq% 127 65500/501 300 119 Under X21 Linear 89 65500/501 300 141 Under X21 Mod Eq% 152 65500/501 300 172 Under X21 Linear 127 65500/501 300 205 Under X21 Linear 152 65990/992 50 4 Under X13 Mod Eq% 28.5 30990/992 50 6 Under X13 Linear 28.5 30990/992 50 6 Under X13 Mod Eq% 38 30990/992 50 7 Under X13 Linear 38 30990/992 80 7 Under X15 Mod Eq% 38 40990/992 80 9 Under X15 Linear 38 40990/992 80 10 Under X15 Mod Eq% 57 40990/992 80 14 Under X15 Linear 57 40990/992 100 15 Under X15 Mod Eq% 57 45990/992 100 22 Under X15 Linear 57 45990/992 150 31 Under X19 Mod Eq% 89 50990/992 150 48 Under X19 Linear 89 50990/992 200 39 Under X21 Mod Eq% 89 55990/992 200 58 Under X21 Mod Eq% 127 55990/992 200 59 Under X21 Linear 89 55990/992 200 73 Under X21 Mod Eq% 152 55990/992 200 86 Under X21 Linear 127 55990/992 200 102 Under X21 Linear 152 55990/992 250 63 Under X21 Mod Eq% 89 60990/992 250 89 Under X21 Linear 89 60990/992 250 92 Under X21 Mod Eq% 127 60990/992 250 115 Under X21 Mod Eq% 152 60990/992 250 129 Under X21 Linear 127 60990/992 250 154 Under X21 Linear 152 60990/992 300 75 Under X21 Mod Eq% 89 65990/992 300 111 Under X21 Mod Eq% 127 65990/992 300 119 Under X21 Linear 89 65990/992 300 141 Under X21 Mod Eq% 152 65990/992 300 172 Under X21 Linear 127 65990/992 300 205 Under X21 Linear 152 65

Customer Scheme Size Rating Application Inlet Pressure Pressure Drop(Bar A) (Bar)

Hopkinsons Ltd Yancheng P.S 4” ANSI 1500 Water 176 167

Atwood & Morrill Nepco -Quachita Power 2” ANSI 2500 Spray Water 139 138

NPCC/Sigma-Abudhabi ONGC ZA Platform 1” ANSI 900 Injection Water 112 99

A.S.E. PKN Orlen (Plock Refinery) 10” ANSI 600 Liquid 64 59

Weir Pumps Ltd Hangcheng P.S 6” ANSI 2500 Water 243 226



Score (Europe) Ltd BP Mungo 1” ANSI 2500 HC Gas 203 202



Atwood & Morrill Ocean States Power 2” ANSI 900 Spray Water 126 125

PNE Aps Halfdan Phase 3 6” ANSI 2500 Sea Water 281 140

Korea South East Power Co Yongchung-Do Units 1 & 2 1” ANSI 4500 Steam 150 149

Korea South East Power Co Yongchung-Do Units 1 & 2 6” ANSI 4500 Water 429 417




LTS Shell Mars 4” API 10000 Sea Water 511 510

Hops Beijing Shizhuishan Power Station 4” ANSI 2000 Water 264 249

WVC S.E.Asia Unknown 2” ANSI 1500 Water 193 171

Skanska Whessoe Ltd Grain LNG Importation Facility 8” ANSI 600 NG Gas 76 75

Skanska Whessoe Ltd Grain LNG Importation Facility 8” ANSI 600 NG Gas 76 75

BP Angola BP Angola Greater Plutonio BLK 18 6” ANSI 2500 Hydrocarbon 371 155

BP Angola BP Angola Greater Plutonio BLK 18 6” ANSI 2500 Hydrocarbon 371 155

BP Angola BP Angola Greater Plutonio BLK 18 8” ANSI 2500 Injection Water 271 180



BP Angola BP Angola Greater Plutonio BLK 18 1” ANSI 2500 Methanol 331 328

British Energy Gen Ltd Dungeness B PS 2” ANSI 4500 Steam 160 158

Barking Power Ltd Barking Power Ltd 2” ANSI 900 Water 98 91

Prometal APS Maersk Tyra East 3” ANSI 1500 HC Liquid + Sand 91 85

Paydar Poolad Pishro Co. “Homa Manifold, Iran” 1” ANSI 1500 Oil & Water 120 115

Part Technologists Nioc Varavi Manifold. 1” ANSI 1500 Oil & Water 120 115

Larsen & Toubro Ltd Mol Pumps - BHN Platform 6” ANSI 900 Oil & Water 78 73

Weir Eng.Pty Ltd Kaeng Khoi 2 Power Plant 3” ANSI 2500 Feedwater 217 143

Prometal APS Prometal APS 4” ANSI 900 Water 126 122

Mehras Aghajari Gas Inj Project 4” ANSI 2500 Hydrocarbon 259 258

Mehras Aghajari Gas Inj Project 6” ANSI 2500 Hydrocarbon 259 258

BP BP Colombia Ltd 6” API 10000 Produced Water 366 296

Daelim Industrial Co Limited South Pars Phase 1 4” ANSI 600 Lean Amine Liquid 85 82

Formosa Heavy Industries Corp Nan Ya Plastics - JH 2 3” ANSI 1500 Steam 128 114

Saipem S.A. Guangdong LNG 3” ANSI 900 LNG 108 106

Saipem S.A. Guangdong LNG 3” ANSI 900 LNG 129 114

Hyundai Heavy Industries Co Ltd Hyundai Heavy Iindustries Co Ltd 4” ANSI 900 Oil & Water 107 101

Khishavand Tasisat Co Khishavand Tasisat Co 4” ANSI 900 Gas 102 98

PT. Valveindo Teknik Pratama PT. Valveindo Teknik Pratama 2” ANSI 1500 Water 151 80

Salzgitter Mannesmann UK Limited South Pars Offshore 6” ANSI 900 HC Gas 113 107

Technip France AKPO 6” ANSI 600 Water 80 71

Scottish & Southern Keadby Power Station 8” ANSI 2500 Feedwater 155 122

Kosep Youngheung Do Power Complex 6” ANSI 2500 Feedwater 135 131

Table 5 – X-Stream™ Installed Severe Service Valves

Blakeborough X-STREAM™ TABLES


Sales/manufacturing:

Weir Valves & Controls UK LtdTel: +44 (0) 1422 282000Fax: +44 (0) 1422 282100Email: [email protected]

Weir Valves & Controls France SASSebim siteTel: +33 (0) 4 42 07 00 95Fax: +33 (0) 4 42 07 11 77Email: [email protected] siteTel: +33 (0) 3 21 79 54 50Fax: +33 (0) 3 21 28 62 00Email: [email protected]

Weir Valves & Controls USA IncTel: +1 978 744 5690Fax: +1 978 741 3626Email: [email protected]

Regional sales offices:

CanadaTel: +1 905 812 0881Fax: +1 905 812 0069Email: [email protected]

ChinaTel: +86 10 8528 8315-7Fax: +86 10 8528 8318Email: [email protected]

MalaysiaTel: +60 3 2287 3560Fax: +60 3 2287 3561Email: [email protected]

Middle EastTel: +971 4 883 6396Fax: +971 4 883 6126Email: [email protected]

KoreaTel: +82 31 493 7979Fax: +82 31 495 3737Email: [email protected]

AustraliaTel: +61 2 4349 2999Fax:+61 2 4349 2900Email: [email protected]

South AfricaTel: +27 1 1929 2906Fax:+27 1 1929 2925Email: [email protected]

Division head office:

Weir Valves & ControlsTel: +44 (0)1484 824200Fax: +44 (0)1484 824230Email: [email protected]

Local Representative

A list of worldwide agents is available onrequest

Weir Valves & Controls UK Ltd

Britannia HouseHuddersfield RoadElland, West YorkshireHX5 9JR England

Tel: +44 (0) 1422 282 000Fax: +44 (0) 1422 282 100Email: [email protected]

ExcellentEngineeringSolutions

XS

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